1. Field of the Invention
The present invention relates generally to exercise and rehabilitation machines. More particularly, the invention relates to a self-adjusting apparatus that is capable of producing and measuring 0-100% of maximum voluntary eccentric, concentric, and static muscular contractions of an individual while exercising or rehabilitating.
2. Description of the Related Art
Various exercise machines have been developed to exercise certain types of human body muscles. These machines are categorized into two broad groups: 1) compound machines which exercise multiple pairs of muscles at the same time and 2) isolation machines which exercise only one pair of muscles at a time. In either case the actual exercise occurs with the movement and contraction of the muscles against an opposing force. The effectiveness of the machine in meeting the specific needs of the user will depend on the quality of interaction between the machine and its user.
The human body muscle is capable of three distinct types of contractions. The first is a positive or concentric function in which the muscle contracts under a load that is less than the muscle strength. The second is a static or isometric function in which the muscle attempts to contract against a load that is greater than the muscle strength. The third is a negative or eccentric function in which an external load is large enough to overcome the muscle strength and force the muscle to elongate in spite of an attempt by the person to contract the muscle.
It is well known that the muscles perform much more efficiently during eccentric functions than during concentric or isometric functions. This is because the same muscle is capable of exerting greater force during its eccentric function than it can during either concentric or isometric functions. Further, concentric and isometric functions results in a comparatively greater expense of energy and stress to the nervous system than eccentric functions, resulting in greater stress to the overall body for the same work out. For this reason, eccentric contraction exercises are preferable from a rehabilitative stance since it produces the much desired benefits of strength building and injury prevention at a much lower metabolic cost with less demand on the cardiovascular and pulmonary systems of the body.
Various types of muscle strengthening equipment have been developed over the years but few take advantage of the varying efficiencies in muscle physiology during motion. These include simple conventional barbells to prohibitively expensive hydraulics. These machines are generally limited to one particular muscle, requiring the purchase of a complete line of machines, which can be very expensive and can occupy a large amount of space. The inconvenience from the lack of versatility in the foregoing machines is experienced at a greater level by physically disabled users, their therapists and trainers. The current rehabilitation equipment available for physically disabled users, particularly those who are wheel chair bound, often require additional handling assistance and do not permit autonomy of use. The difficulty of handling by disabled users often leads to injury, feelings of dependence and frustration which leads to depression.
With few exceptions, prior art exercise and rehabilitation machines continue to be cost prohibitive, non-versatile and fail to maximize on the user's potential workout by exploring the full range muscle functions discussed above. An improvement on these combinations of features would be ideal.
Almost all known prior machines impose a single load that the person must overcome during both concentric and eccentric muscle functions. A few machines are capable of imposing different loads for concentric and eccentric muscle functions, but those machines invariably include very expensive and complicated hydraulic systems.
Examples of prior mechanical exercise machines are plentiful. The Nautilus Co., among others, employ the use of spiral cams in their machines to accommodate the force curves that take place as muscles lengthen and leverage changes occurring during a concentric contraction. However, these machines do not address the difference in performance between concentric, static and eccentric contractions.
Other commercially available exercise machines utilize guided sliding weight stacks. In these machines, the weight can only be changed in between exercise repetitions but not during. Many other styles of commercial exercise machines such as lever based weight machines and plate-loaded machines suffer the same problem in that the inability to manipulate weights during exercise repetitions prohibits the machine from taking advantage of the user's full work out potential as it relates to the various muscle functions.
Examples of lever based machines include the standard bench press, as ones marketed by the Powertec Direct Company. Somewhat similar equipment is shown in PCT patent WO89/01805. Other examples of beam and weight type exercising machines may be seen in U.S. Pat. Nos. 5,050,873; 5,066,003; 5,125,881; 5,135,449; 5,135,456; 5,171,198; 5,180,354; 5,181,896; 5,273,504; 5,273,505; and Des 321,391. No machine of the foregoing patents gives any indication that different loads should be overcome by the user during concentric and eccentric functions.
U.S. Pat. No. 4,826,155 shows equipment that takes into account the inherent ability of human muscles to perform differently during concentric and eccentric functions. This patent shows a harness worn by the user that is tied with a rope through a block and tackle to assist the user in raising weights during concentric muscle functions. During eccentric muscle functions, a spotter allows an increased load to be imposed on the user.
My earlier patent, U.S. Pat. No. 7,070,543, is a recent invention which does attempt to maximize on the benefits between concentric, isometric and eccentric contractions. The device is a compound weight machine with leverage arms pivoted to a frame. A small force is applied while the lever is in a raised position, imposing an additional load that the user must resist during the eccentric muscle function. The manipulation of weights during each repetition allows the user to maximize his potential concentric and eccentric exertion potential. However, since the variation in load is based on preset weights, it is difficult to measure gradual real time changes in the user's voluntary muscle contraction during exercise. Further, the machine is not self adjustable because it requires assistance of a second party spotter to apply additional loads during repetitions to accomplish the intentions of the machine.
The counterpart to the above referenced compound exercise machine is an isolated exercise machine, U.S. Pat. No. 7,070,544, which maximizes the benefits between concentric, isometric and eccentric contractions. The device comprises a bench style work station with a leverage arm that rotates in unison with one or the other of two force stations. A spotter applies a small force to the leverage arm in its raised position, creating an amplified force against the working muscles during eccentric contractions. As with its counterpart in the above referenced patent, this invention functions manually and is not self-adjusting. Similarly, changes in performance during exercise are limited by the preset loads of the weights. The inability to achieve more accurate real time measurements limits the ability of physical trainers and therapists to control their client's rehabilitation process.
None of the above-patents show a user adjustable machine that is controlled by the user.
Further, none show a machine that has a drive assembly that is controlled at the handle by the user.
Still further, none show a machine that has a drive assembly that is wirelessly controlled by the user.
Still further yet, none show a spool that selectably winds and unwinds.
Still further yet, none show a spool that can utilize a variable amount of force as adjusted by the user during an exercise.
Still further yet, none show a dual or compound drive assembly that is selectably adjustable between a vertical frame and a horizontal frame.
Still further yet, none show a frame having guide posts that allow the user to select from multiple exercises based on use of either the vertical or horizontal frame.
Still further yet, none show a force transducer and converter that converts to standard units to provide real-time feedback to the user.
Still further yet, none show a machine that is adapted for removal of the seat assembly for use with a wheel chair.
Thus there exists a need for a user controlled exercise machine that solves these and other problems.